Venkatesan, Thangam

ABSTRACTBackgroundData are limited on the natural history and symptom patterns of cyclic vomiting syndrome (CVS), a disorder of gut–brain interaction characterized by recurrent stereotypical vomiting, retching, and nausea episodes.MethodsA 6‐month, observational, remote study prospectively assessed symptom patterns in adults with CVS using an electronic daily diary. Patients recorded their disease experience, including CVS symptoms and associated severity, in the daily diary. The study defined a CVS episode start as the first day of 5 or more vomiting and/or retching (V + R) events. Episode end was defined as the first day of ≥ 7 (prespecified main analysis) or ≥ 4 (sensitivity analysis) days without any diary V + R events.Key ResultsEighty‐eight of 93 (94.6%) enrolled patients (62 female; mean age, 37.7 years) had daily diary data recorded during the study; 61 (69.3%) patients had at least one episode. In the prespecified main analysis, 191 episodes (median, 0.6 per 30 diary days) were reported (median duration, 3.0 days); 17.8% of the episodes lasted > 10 days. In the sensitivity analysis, 248 episodes (median, 0.7 per 30 diary days) were reported (median duration, 2.0 days). Thirteen of 88 (14.8%) patients with diary data had interepisodic V + R (reported V + R events without meeting the threshold for study‐defined episode). Other CVS‐related (non‐V + R) symptoms (most frequently nausea, abdominal pain, and sweating) were reported more frequently during the episode versus the interepisodic period.Conclusions and InferencesThis prospective longitudinal study shows marked heterogeneity of CVS episodes and highlights the need to better define and characterize episodes in these patients.

Abstract Background Cannabis use in the general population is prevalent and is rising because of increased acceptance of its use, legalization in most US states, and perceived health benefits. Cannabis product potency has dramatically increased with higher delta‐9‐tetrahydrocannabinol content. Cannabis has documented antiemetic properties and cannabinoid pharmaceuticals are used in disorders like chemotherapy‐induced nausea and vomiting. Purpose Forty to eighty percent of cyclic vomiting syndrome (CVS) patients use cannabis products, which reportedly reduce stress as well as nausea and vomiting. Cannabinoid hyperemesis syndrome (CHS) has a presentation similar to CVS, but is associated with longstanding, high dose cannabis use, and is thought to be relieved by sustained cannabis abstinence. Most CHS patients have used cannabis on a daily or near‐daily basis for more than 2 years. Compulsive hot‐water bathing behaviors are reported by most CHS patients, but are not specific for this disorder as they are also noted by about half of CVS patients. Episodic vomiting associated with cannabis use contributes to extensive health resource use, including emergency department visits and inpatient hospitalizations, and impacts patients and their families negatively. Treatment for CHS overlaps with CVS although cannabis abstinence remains the cornerstone of its management. Challenges associated with cannabis use cessation in CHS include patient skepticism of the role of cannabis as a cause of symptoms, perceived benefits of cannabis, and a lack of other effective therapies. In this review, we highlight cannabis use patterns in the US and discuss diagnosis and management of CHS and gaps in knowledge about this disorder.

AbstractBackgroundAn increasing number of studies have explored the clinical features, epidemiology, pathophysiology, and management of cyclic vomiting syndrome (CVS). CVS is common in adults and children and negatively impacts patients, families, and the healthcare system. A related condition, cannabinoid hyperemesis syndrome (CHS), has been a focus of interest in the lay press and published literature.PurposeClinical presentations of CVS have been defined by small series and expert opinion, but recent prospective studies are refining our understanding of the spectrum of emetic episodes and the breadth of comorbid conditions. Large cross‐sectional population analyses are clarifying CVS prevalence and factors related to age, ethnicity, and geographic region. CVS pathophysiology is multifactorial with contributions from migraines, dysautonomia, endogenous cannabinoids, mitochondrial dysfunction, genetic abnormalities, and rapid gastric emptying. CVS treatment relies on antiemetics and antimigraine therapies to abort acute episodes coupled with prophylactic regimens employing neuromodulators and antiepileptics. CHS represents a challenge partly because of difficulties in achieving sustained cannabis abstinence. Benefits of other therapies in CHS remain poorly defined. Several areas warrant further scrutiny including better identification of CVS triggers and characterization of different CVS subsets including those with frequent severe episodes, refined description of epidemiology to allow targeting of populations predisposed to CVS development, rigorous definition of pathogenic factors to provide a foundation for exploratory studies of novel therapies, and conduct of controlled trials by multicenter collaborations to confirm benefits of existing and new therapies in development. Progress in these areas will be facilitated by generous governmental and industry support.

Cyclic vomiting syndrome (CVS) is a chronic disorder of gut-brain interaction characterized by recurrent disabling episodes of nausea, vomiting, and abdominal pain. CVS affects both children and adults with a prevalence of approximately 2% in the United States. CVS is more common in female individuals and affects all races. The pathophysiology of CVS is unknown and a combination of genetic, environmental, autonomic, and neurohormonal factors is believed to play a role. CVS is also closely associated with migraine headaches and likely have a shared pathophysiology. The diagnosis of CVS is based on the Rome criteria, and minimal recommended testing includes an upper endoscopy and imaging studies of the abdomen. CVS is frequently associated with anxiety, depression, and autonomic dysfunction. Patients with CVS commonly use cannabis therapeutically for symptom relief. By contrast, cannabinoid hyperemesis syndrome is believed to be a subset of CVS with chronic heavy cannabis use leading to hyperemesis. Due to the recalcitrant nature of the illness, patients often visit the emergency department and are hospitalized for acute CVS flares. Guidelines on the management of CVS recommend a biopsychosocial approach. Prophylactic therapy consists of tricyclic antidepressants (amitriptyline), antiepileptics (topiramate), and aprepitant in refractory patients. Abortive therapy consists of triptans, antiemetics (ondansetron), and sedation. Treatment of comorbid conditions is extremely important to improve overall patient outcomes. CVS has a significant negative impact on patients, families, and the healthcare system, and future research to understand its pathophysiology and develop targeted therapies is needed.